Traditional manual bicycle operations involve the utilization of a chain to allow for transfer of power from a pedal gear to a wheel gear to provide the necessary rotational energy for vehicle propulsion. Such standard devices generally require the user to “stand” on the vehicle to provide suitable torque to the pedals for sufficient force for motion to occur. The chain component drives a rear wheel in such an operation while the front wheel is present for balance and steering purposes with a handlebar configuration for control. Unicycles and tricycles typically utilize pedal cranks on opposing sides of a wheel (front for a typical tricycle) where the user's feet generate power directly through a axis representing the center of the wheel itself. Such activities are generally difficult to undertake as the capabilities of the user to generate sufficient force for certain speeds and/or to maneuver the vehicle up an incline are substantial. Additionally, such a pedal crank configuration requires the pedaling and steering capabilities to reside in the same plane, making the overall activity taxing on the user. If pedaling occurs during turning, the user's legs must adjust to differing angles and lengths until the direction is straightened. With the necessity to provide varying forces to either pedal while in the middle of a turn, as well, steering may be compromised to a certain extent as well, requiring the user to compensate for such potential difficulties.
As it is, some developments have been provided to permit reduced force for increased bicycle velocities (or improved incline climbing capability), such as the utilization of multiple gears for shifting between “low” and “high” torque generation levels. These improvements, however, still rely upon the involvement of a chain assembly and, more so, require the cyclist to remain in an upright position thereby generating force through a combination of muscle and gravity. Tricycle and unicycle devices have not been improved to any such extent, except for the involvement of chain assemblies in certain circumstances which, again, revert back to the traditional types of cycles.
Recumbent bicycles have been available within the industry for quite some time, providing a unique alternative to the upright cycling position with resultant potential exercise workout improvements for such users. These devices, however, still primarily involve the utilization of chains to transmit suitable drive power from front-positioned pedals to a rear wheel. In any event, there still remains a rather limited extent of cycle device configurations with the vast majority still reliant on old chain-based technology.
There have also been front-wheel powered chain assemblies undertaken within the cycling industry, as well. These unique constructions, however, require problematic configurations whereby, for example, the chain is either twisted across a plane of steering rotation, or a universal joint is used to bridge both moving (rotating about steering axis) and non-moving drive shaft axes. In either case, the resultant steering motion is compromised significantly, and particularly in comparison with traditional, rear-wheel drive bicycles. Such issues may deleteriously impact the stability of such a device as well as severely restrict its maneuverability, too. As such, these configurations are functionally deficient due to misapplication of the power transmission technologies employed. In particular, such power drive chains exhibit small allowable range of angular deflection within useful torque transmission limits due to the odd configurations of chain movement involved.
There have been some other developments that have taken into consideration the capabilities of epicyclic gear configurations for power transmission within a cycling operation. To that end, such devices tend to utilize a gear train to transmit power across a plane of steering rotation by use of a sun gear coaxial to a steering axis. In principle, this arrangement may allow relatively unrestricted steering, with a further benefit of a high efficiency spur gear transmission. This configuration may overcome, to a limited extent, certain problems of interference with manual steering induced by drive torque reactions within an epicyclic transmission arrangement through the inclusion of dual, counter-rotating sun gears. In this manner, parallel and opposite transmission paths to a front wheel hub axis are permitted which, in theory, imparts a remedial reaction force imparted to a steering fork to evenly divide into opposing and canceling components. However, in practice such an overall design would actually work to favor power transmission through one path over another; such force divisions then would appear to result in dominance of one over the other instead of an evenly shared undertaking by both available structures. The resultant canceling effect would thus be compromised or even lost entirely in that scenario. There is no remedy for such problems through, for instance, a significant torque-reduction between epicyclic gears and a pedal crank, let alone through any other accompanying compensation of torque multiplication between epicyclic gears and a driven wheel. In other words, the high torque required of such a past epicyclic gear configuration still results in a significantly high required torque for operation, leaving such power generation on the user to provide. Likewise, a failure of theoretical torque-reaction canceling may result in significant, unbalanced force acting on a steering fork. Normal fluctuations in input torque and/or rolling resistance of a driven wheel will cause like fluctuations in such a force, tending to change a steering direction unless sufficiently countered by a control reaction of an operator. It is likely that such forces can be sufficient under certain circumstances to cause loss of control by an operator.
Thus, what remains is a distinct need to provide a cycle device (bicycle, tricycle, for instance) that allows for a user to utilize low power generation for proper motion to occur for cycle movement to climb inclines or achieve higher speeds while the torque necessary for such a result does not impede the steering capability thereof, simultaneously. To date, as noted above, this result has yet to be provided within the pertinent prior art.